What do the Statue of Liberty, the Brooklyn Bridge, Grand Central Station and the White House all have in common? If you are an Ulster County resident that answer is simple — Ulster County Natural Concrete. Until the 19th century, building projects of this scale were impossible in North America due to a lack of materials that would somehow withstand nature’s forces.

Thanks to one Canvass White (1790-1834) and his patent for the first natural cement factory in the United States, the engineering of large-scale complexes suddenly became a possibility. Unlike other high-quality mortars at that time, natural concrete was able to harden under water. Made from clay rich dolostone and limestone, Ulster County boasted the motherlode of both materials.

Rosendale was especially rich in high quality limestone, which was unearthed around 1825 when the Delaware & Hudson Canal was being excavated. The deposit was so vast it extended 32 square miles from High Falls to Kingston and was 22 feet in depth. White moved quickly when the enormous vein was uncovered. He relocated his operation from Chittenango, N.Y. to Whiteport, near Rosendale.

Of course, competition was fierce and by 1840 there were no less than a dozen companies shipping “Rosendale Cement” down the D & H Canal and the Rondout Creek to the Hudson River for use all over the country via the Atlantic Ocean. Almost every single important building project of the era owed their engineering to the binder. Cement mined from the Snyder Estate’s Widow Jane Mine, one of the best known in Rosendale, was shipped to create the base of Lady Liberty herself.

In Kingston, many cement factories took root. The Newark Lime and Cement Company began operations in the Rondout in 1851 and was by far the most important in that area. Composed of 250 acres, including waterfront property on the creek, it alone produced over 200,000 barrels of the material. Twenty-one kilns were employed for burning stone with enough storage to hold up to 20,000 barrels at a time. Some 250-300 men worked daily at the enormous plant.

By the end of the 19th century, Rosendale Cement companies were shipping nearly 10 million barrels a year from their facilities. While it seemed that there was no end to the success of the material, a newfangled version was waiting in the wings. Portland Cement was even stronger and soon became the most popular version of the plaster. Rosendale Cement held on as a specialty product until 1970, when the last mine closed its doors forever.

In the 1930’s, two brothers took advantage of the cave system left by the cement industry. Herman and Henry Knaust were pioneers of the mushroom industry. The abandoned mines were a perfect fit for the brothers’ business, providing the perfect growing climate for the fungi. Fifteen million pounds were grown annually and gave thousands of residents jobs both in farming and in the canning industry.

Later the mines were used for a storage facility called Iron Mountain. Today, they sit dormant waiting for their next best incarnation.

The Century House maintains a museum on the history of the Snyder Estate, the industrial history of the Rosendale Cement District and Rosendale history in general. Visit https://www.centuryhouse.org/visit/ for more information.